Your first treatment is extract your wisdom tooth and reddish black discoloration may be because of cheek bite caused due to this wisdom tooth , but without a clinical examination we cant diagnose what it is!...
Kindly consult with a dentist, have a clinical examination and extract your wisdom tooth...
Hope so you will be fine after this treatment..
Next Steps
Don't delay your treatment of wisdom tooth because it weakens the adjacent tooth...
Health Tips
While eating, have a caution that you don't bite your cheek often....